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<tr class="t-nv"><td colspan="5"> <strong class="selflink">Copy assignment operator</strong></td></tr>
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<p>A copy assignment operator of class <code>T</code> is a non-template <a href="member_functions.html" title="cpp/language/member functions">non-static member function</a> with the name <span class="t-c"><span class="mw-geshi cpp source-cpp">operator<span class="sy1">=</span></span></span> that takes exactly one parameter of type <span class="t-c"><span class="mw-geshi cpp source-cpp">T</span></span>, <span class="t-c"><span class="mw-geshi cpp source-cpp">T<span class="sy3">&amp;</span></span></span>, <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">const</span> T<span class="sy3">&amp;</span></span></span>, <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">volatile</span> T<span class="sy3">&amp;</span></span></span>, or <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">const</span> <span class="kw4">volatile</span> T<span class="sy3">&amp;</span></span></span>. For a type to be <a href="../named_req/CopyAssignable.html" title="cpp/named req/CopyAssignable"><span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">CopyAssignable</span></a>, it must have a public copy assignment operator.
</p>
<h3><span class="mw-headline" id="Syntax">Syntax</span></h3>
<table class="t-sdsc-begin">

<tr>
<td colspan="10" class="t-sdsc-sep">
</td></tr>
<tr class="t-sdsc">
<td> <span class="t-spar">class-name</span> <code><b>&amp;</b></code> <span class="t-spar">class-name</span> <code><b>::</b></code> <code><b>operator=</b></code> ( <span class="t-spar">class-name</span> )
</td>
<td> (1)
</td>
<td class="t-sdsc-nopad">
</td></tr>

 

<tr>
<td colspan="10" class="t-sdsc-sep">
</td></tr>
<tr class="t-sdsc">
<td> <span class="t-spar">class-name</span> <code><b>&amp;</b></code> <span class="t-spar">class-name</span> <code><b>::</b></code> <code><b>operator=</b></code> ( <code><b>const</b></code> <span class="t-spar">class-name</span> <code>&amp;</code> )
</td>
<td> (2)
</td>
<td class="t-sdsc-nopad">
</td></tr>

 

<tr>
<td colspan="10" class="t-sdsc-sep">
</td></tr>
<tr class="t-sdsc">
<td> <span class="t-spar">class-name</span> <code><b>&amp;</b></code> <span class="t-spar">class-name</span> <code><b>::</b></code> <code><b>operator=</b></code> ( <code><b>const</b></code> <span class="t-spar">class-name</span> <code>&amp;</code> ) = <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">default</span><span class="sy4">;</span></span></span>
</td>
<td> (3)
</td>
<td> <span class="t-mark-rev t-since-cxx11">(since C++11)</span>
</td></tr>



<tr>
<td colspan="10" class="t-sdsc-sep">
</td></tr>
<tr class="t-sdsc">
<td> <span class="t-spar">class-name</span> <code><b>&amp;</b></code> <span class="t-spar">class-name</span> <code><b>::</b></code> <code><b>operator=</b></code> ( <code><b>const</b></code> <span class="t-spar">class-name</span> <code>&amp;</code> ) = <span class="t-c"><span class="mw-geshi cpp source-cpp">delete<span class="sy4">;</span></span></span>
</td>
<td> (4)
</td>
<td> <span class="t-mark-rev t-since-cxx11">(since C++11)</span>
</td></tr>



<tr>
<td colspan="10" class="t-sdsc-sep">
</td></tr></table>
<h3><span class="mw-headline" id="Explanation">Explanation</span></h3>
<div class="t-li1"><span class="t-li">1)</span> Typical declaration of a copy assignment operator when <a href="operators.html#Assignment_operator" title="cpp/language/operators">copy-and-swap idiom</a> is used.</div>
<div class="t-li1"><span class="t-li">2)</span> Typical declaration of a copy assignment operator when copy-and-swap idiom is not used.</div>
<div class="t-li1"><span class="t-li">3)</span> Forcing a copy assignment operator to be generated by the compiler.</div>
<div class="t-li1"><span class="t-li">4)</span> Avoiding implicit copy assignment.</div>
<p>The copy assignment operator is called whenever selected by <a href="overload_resolution.html" title="cpp/language/overload resolution">overload resolution</a>, e.g. when an object appears on the left side of an assignment expression.
</p>
<h3><span class="mw-headline" id="Implicitly-declared_copy_assignment_operator">Implicitly-declared copy assignment operator</span></h3>
<p>If no user-defined copy assignment operators are provided for a class type (<span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">struct</span></span></span>, <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">class</span></span></span>, or <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">union</span></span></span>), the compiler will always declare one as an inline public member of the class. This implicitly-declared copy assignment operator has the form <span class="t-c"><span class="mw-geshi cpp source-cpp">T<span class="sy3">&amp;</span> T<span class="sy4">::</span><span class="me2">operator</span><span class="sy1">=</span><span class="br0">(</span><span class="kw4">const</span> T<span class="sy3">&amp;</span><span class="br0">)</span></span></span> if all of the following is true:
</p>
<ul><li> each direct base <code>B</code> of <code>T</code> has a copy assignment operator whose parameters are <span class="t-c"><span class="mw-geshi cpp source-cpp">B</span></span> or <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">const</span> B<span class="sy3">&amp;</span></span></span> or <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">const</span> <span class="kw4">volatile</span> B<span class="sy3">&amp;</span></span></span>;
</li><li> each non-static data member <code>M</code> of <code>T</code> of class type or array of class type has a copy assignment operator whose parameters are <span class="t-c"><span class="mw-geshi cpp source-cpp">M</span></span> or <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">const</span> M<span class="sy3">&amp;</span></span></span> or <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">const</span> <span class="kw4">volatile</span> M<span class="sy3">&amp;</span></span></span>.
</li></ul>
<p>Otherwise the implicitly-declared copy assignment operator is declared as <span class="t-c"><span class="mw-geshi cpp source-cpp">T<span class="sy3">&amp;</span> T<span class="sy4">::</span><span class="me2">operator</span><span class="sy1">=</span><span class="br0">(</span>T<span class="sy3">&amp;</span><span class="br0">)</span></span></span>. (Note that due to these rules, the implicitly-declared copy assignment operator cannot bind to a volatile lvalue argument.)
</p><p>A class can have multiple copy assignment operators, e.g. both <span class="t-c"><span class="mw-geshi cpp source-cpp">T<span class="sy3">&amp;</span> T<span class="sy4">::</span><span class="me2">operator</span><span class="sy1">=</span><span class="br0">(</span>T<span class="sy3">&amp;</span><span class="br0">)</span></span></span> and <span class="t-c"><span class="mw-geshi cpp source-cpp">T<span class="sy3">&amp;</span> T<span class="sy4">::</span><span class="me2">operator</span><span class="sy1">=</span><span class="br0">(</span>T<span class="br0">)</span></span></span>. <span class="t-rev-inl t-since-cxx11"><span>If some user-defined copy assignment operators are present, the user may still force the generation of the implicitly declared copy assignment operator with the keyword <code>default</code>.</span> <span><span class="t-mark-rev t-since-cxx11">(since C++11)</span></span></span>
</p><p>The implicitly-declared (or defaulted on its first declaration) copy assignment operator has an exception specification as described in <span class="t-rev-inl t-until-cxx17"><span><a href="except_spec.html" title="cpp/language/except spec">dynamic exception specification</a></span> <span><span class="t-mark-rev t-until-cxx17">(until C++17)</span></span></span><span class="t-rev-inl t-since-cxx17"><span><a href="noexcept_spec.html" title="cpp/language/noexcept spec">noexcept specification</a></span> <span><span class="t-mark-rev t-since-cxx17">(since C++17)</span></span></span>
</p><p>Because the copy assignment operator is always declared for any class, the base class assignment operator is always hidden. If a <a href="using_declaration.html#In_class_definition" title="cpp/language/using declaration">using-declaration</a> is used to bring in the assignment operator from the base class, and its argument type could be the same as the argument type of the implicit assignment operator of the derived class, the using-declaration is also hidden by the implicit declaration.
</p>
<h3><span class="mw-headline" id="Deleted_implicitly-declared_copy_assignment_operator">Deleted implicitly-declared copy assignment operator</span></h3>
<p>An implicitly-declared copy assignment operator for class <code>T</code> is defined as <i>deleted</i> if any of the following is true:
</p>
<ul><li> <code>T</code> has a user-declared move constructor;
</li><li> <code>T</code> has a user-declared move assignment operator.
</li></ul>
<p>Otherwise, it is defined as defaulted. 
</p><p>A defaulted copy assignment operator for class <code>T</code> is defined as <i>deleted</i> if any of the following is true:
</p>
<ul><li> <code>T</code> has a non-static data member of non-class type (or array thereof) that is <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">const</span></span></span>;
</li><li> <code>T</code> has a non-static data member of a reference type;
</li><li> <code>T</code> has a non-static data member or a direct base class that cannot be copy-assigned (overload resolution for the copy assignment fails, or selects a deleted or inaccessible function);
</li><li> <code>T</code> is a <a href="union.html#Union-like_classes" title="cpp/language/union">union-like class</a>, and has a variant member whose corresponding assignment operator is non-trivial.
</li></ul>
<h3><span class="mw-headline" id="Trivial_copy_assignment_operator">Trivial copy assignment operator</span></h3>
<p>The copy assignment operator for class <code>T</code> is trivial if all of the following is true:
</p>
<ul><li> it is not user-provided (meaning, it is implicitly-defined or defaulted);
</li><li> <code>T</code> has no virtual member functions;
</li><li> <code>T</code> has no virtual base classes;
</li><li> the copy assignment operator selected for every direct base of <code>T</code> is trivial;
</li><li> the copy assignment operator selected for every non-static class type (or array of class type) member of <code>T</code> is trivial.
</li></ul>
<p>A trivial copy assignment operator makes a copy of the object representation as if by <span class="t-lc"><a href="../string/byte/memmove.html" title="cpp/string/byte/memmove">std::memmove</a></span>. All data types compatible with the C language (POD types) are trivially copy-assignable.
</p>
<h3><span class="mw-headline" id="Eligible_copy_assignment_operator">Eligible copy assignment operator</span></h3>
 <table class="t-rev-begin">
<tr class="t-rev t-until-cxx11"><td>
<p>A copy assignment operator is eligible if it is either user-declared or both implicitly-declared and definable.
</p>
</td>
<td><span class="t-mark-rev t-until-cxx11">(until C++11)</span></td></tr>
<tr class="t-rev t-since-cxx11 t-until-cxx20"><td>
<p>A copy assignment operator is eligible if it is not deleted.
</p>
</td>
<td><span class="t-mark-rev t-since-cxx11">(since C++11)</span><br><span class="t-mark-rev t-until-cxx20">(until C++20)</span></td></tr>
<tr class="t-rev t-since-cxx20"><td>
<p>A copy assignment operator is eligible if
</p>
<ul><li> it is not deleted, and
</li><li> its <a href="constraints.html" title="cpp/language/constraints">associated constraints</a>, if any, are satisfied, and
</li><li> no copy assignment operator with the same first parameter type and the same cv/ref-qualifiers (if any) is <a href="constraints.html#Partial_ordering_of_constraints" title="cpp/language/constraints">more constrained</a> than it.
</li></ul>
</td>
<td><span class="t-mark-rev t-since-cxx20">(since C++20)</span></td></tr>
</table>
<p>Triviality of eligible copy assignment operators determines whether the class is a <a href="../named_req/TriviallyCopyable.html" title="cpp/named req/TriviallyCopyable">trivially copyable type</a>.
</p>
<h3><span class="mw-headline" id="Implicitly-defined_copy_assignment_operator">Implicitly-defined copy assignment operator</span></h3>
<p>If the implicitly-declared copy assignment operator is neither deleted nor trivial, it is defined (that is, a function body is generated and compiled) by the compiler if <a href="definition.html#ODR-use" title="cpp/language/definition">odr-used</a><span class="t-rev-inl t-since-cxx14"><span> or <a href="constant_expression.html#Functions_and_variables_needed_for_constant_evaluation" title="cpp/language/constant expression">needed for constant evaluation</a></span> <span><span class="t-mark-rev t-since-cxx14">(since C++14)</span></span></span>. For union types, the implicitly-defined copy assignment copies the object representation (as by <span class="t-lc"><a href="../string/byte/memmove.html" title="cpp/string/byte/memmove">std::memmove</a></span>). For non-union class types (<span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">class</span></span></span> and <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">struct</span></span></span>), the operator performs member-wise copy assignment of the object's bases and non-static members, in their initialization order, using built-in assignment for the scalars and copy assignment operator for class types.
</p>
 <table class="t-rev-begin">
<tr class="t-rev t-since-cxx14"><td>
<p>The implicitly-defined copy assignment operator for a class <code>T</code> is <a href="constexpr.html" title="cpp/language/constexpr"><code>constexpr</code></a> if
</p>
<ul><li> <code>T</code> is a <a href="../named_req/LiteralType.html" title="cpp/named req/LiteralType">literal type</a>, and
</li><li> the assignment operator selected to copy each direct base class subobject is a constexpr function, and
</li><li> for each non-static data member of <code>T</code> that is of class type (or array thereof), the assignment operator selected to copy that member is a constexpr function.
</li></ul>
</td>
<td><span class="t-mark-rev t-since-cxx14">(since C++14)</span></td></tr>
</table>
 <table class="t-rev-begin">
<tr class="t-rev t-since-cxx11"><td>
<p>The generation of the implicitly-defined copy assignment operator is deprecated if <code>T</code> has a user-declared destructor or user-declared copy constructor.
</p>
</td>
<td><span class="t-mark-rev t-since-cxx11">(since C++11)</span></td></tr>
</table>
<h3><span class="mw-headline" id="Notes">Notes</span></h3>
<p>If both copy and move assignment operators are provided, overload resolution selects the move assignment if the argument is an <a href="value_category.html" title="cpp/language/value category"><i>rvalue</i></a> (either a <a href="value_category.html" title="cpp/language/value category"><i>prvalue</i></a> such as a nameless temporary or an <a href="value_category.html" title="cpp/language/value category"><i>xvalue</i></a> such as the result of <span class="t-lc">std::move</span>), and selects the copy assignment if the argument is an <a href="value_category.html" title="cpp/language/value category"><i>lvalue</i></a> (named object or a function/operator returning lvalue reference). If only the copy assignment is provided, all argument categories select it (as long as it takes its argument by value or as reference to const, since rvalues can bind to const references), which makes copy assignment the fallback for move assignment, when move is unavailable.
</p><p>It is unspecified whether virtual base class subobjects that are accessible through more than one path in the inheritance lattice, are assigned more than once by the implicitly-defined copy assignment operator (same applies to <a href="move_operator.html" title="cpp/language/move assignment">move assignment</a>).
</p><p>See <a href="operators.html#Assignment_operator" title="cpp/language/operators">assignment operator overloading</a> for additional detail on the expected behavior of a user-defined copy-assignment operator.
</p>
<h3><span class="mw-headline" id="Example">Example</span></h3>
<div class="t-example"><div class="t-example-live-link"><div class="coliru-btn coliru-btn-run-init">Run this code</div></div>
<div dir="ltr" class="mw-geshi" style="text-align: left;"><div class="cpp source-cpp"><pre class="de1"><span class="co2">#include &lt;iostream&gt;</span>
<span class="co2">#include &lt;memory&gt;</span>
<span class="co2">#include &lt;string&gt;</span>
<span class="co2">#include &lt;algorithm&gt;</span>
 
<span class="kw1">struct</span> A
<span class="br0">{</span>
    <span class="kw4">int</span> n<span class="sy4">;</span>
    <a href="../string/basic_string.html"><span class="kw1233">std::<span class="me2">string</span></span></a> s1<span class="sy4">;</span>
    A<span class="br0">(</span><span class="br0">)</span> <span class="sy1">=</span> <span class="kw1">default</span><span class="sy4">;</span>
    A<span class="br0">(</span>A <span class="kw4">const</span><span class="sy3">&amp;</span><span class="br0">)</span> <span class="sy1">=</span> <span class="kw1">default</span><span class="sy4">;</span>
    <span class="co1">// user-defined copy assignment (copy-and-swap idiom)</span>
    A<span class="sy3">&amp;</span> operator<span class="sy1">=</span><span class="br0">(</span>A other<span class="br0">)</span>
    <span class="br0">{</span>
        <a href="../io/cout.html"><span class="kw1762">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">"copy assignment of A<span class="es1">\n</span>"</span><span class="sy4">;</span>
        <a href="../algorithm/swap.html"><span class="kw1603">std::<span class="me2">swap</span></span></a><span class="br0">(</span>n, other.<span class="me1">n</span><span class="br0">)</span><span class="sy4">;</span>
        <a href="../algorithm/swap.html"><span class="kw1603">std::<span class="me2">swap</span></span></a><span class="br0">(</span>s1, other.<span class="me1">s1</span><span class="br0">)</span><span class="sy4">;</span>
        <span class="kw1">return</span> <span class="sy2">*</span>this<span class="sy4">;</span>
    <span class="br0">}</span>
<span class="br0">}</span><span class="sy4">;</span>
 
<span class="kw1">struct</span> B <span class="sy4">:</span> A
<span class="br0">{</span>
    <a href="../string/basic_string.html"><span class="kw1233">std::<span class="me2">string</span></span></a> s2<span class="sy4">;</span>
    <span class="co1">// implicitly-defined copy assignment</span>
<span class="br0">}</span><span class="sy4">;</span>
 
<span class="kw1">struct</span> C
<span class="br0">{</span>
    <a href="../memory/unique_ptr.html"><span class="kw734">std::<span class="me2">unique_ptr</span></span></a><span class="sy1">&lt;</span><span class="kw4">int</span><span class="br0">[</span><span class="br0">]</span><span class="sy1">&gt;</span> data<span class="sy4">;</span>
    <a href="../types/size_t.html"><span class="kw106">std::<span class="me2">size_t</span></span></a> size<span class="sy4">;</span>
    <span class="co1">// user-defined copy assignment (non copy-and-swap idiom)</span>
    <span class="co1">// note: copy-and-swap would always reallocate resources</span>
    C<span class="sy3">&amp;</span> operator<span class="sy1">=</span><span class="br0">(</span><span class="kw4">const</span> C<span class="sy3">&amp;</span> other<span class="br0">)</span>
    <span class="br0">{</span>
        <span class="kw1">if</span> <span class="br0">(</span>this <span class="sy3">!</span><span class="sy1">=</span> <span class="sy3">&amp;</span>other<span class="br0">)</span> <span class="co1">// not a self-assignment</span>
        <span class="br0">{</span>
            <span class="kw1">if</span> <span class="br0">(</span>size <span class="sy3">!</span><span class="sy1">=</span> other.<span class="me1">size</span><span class="br0">)</span> <span class="co1">// resource cannot be reused</span>
            <span class="br0">{</span>
                data.<span class="me1">reset</span><span class="br0">(</span>new <span class="kw4">int</span><span class="br0">[</span>other.<span class="me1">size</span><span class="br0">]</span><span class="br0">)</span><span class="sy4">;</span>
                size <span class="sy1">=</span> other.<span class="me1">size</span><span class="sy4">;</span>
            <span class="br0">}</span>
            <a href="../algorithm/copy.html"><span class="kw1586">std::<span class="me2">copy</span></span></a><span class="br0">(</span><span class="sy3">&amp;</span>other.<span class="me1">data</span><span class="br0">[</span><span class="nu0">0</span><span class="br0">]</span>, <span class="sy3">&amp;</span>other.<span class="me1">data</span><span class="br0">[</span><span class="nu0">0</span><span class="br0">]</span> <span class="sy2">+</span> size, <span class="sy3">&amp;</span>data<span class="br0">[</span><span class="nu0">0</span><span class="br0">]</span><span class="br0">)</span><span class="sy4">;</span>
        <span class="br0">}</span>
        <span class="kw1">return</span> <span class="sy2">*</span>this<span class="sy4">;</span>
    <span class="br0">}</span>
<span class="br0">}</span><span class="sy4">;</span>
 
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
<span class="br0">{</span>
    A a1, a2<span class="sy4">;</span>
    <a href="../io/cout.html"><span class="kw1762">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">"a1 = a2 calls "</span><span class="sy4">;</span>
    a1 <span class="sy1">=</span> a2<span class="sy4">;</span> <span class="co1">// user-defined copy assignment</span>
 
    B b1, b2<span class="sy4">;</span>
    b2.<span class="me1">s1</span> <span class="sy1">=</span> <span class="st0">"foo"</span><span class="sy4">;</span>
    b2.<span class="me1">s2</span> <span class="sy1">=</span> <span class="st0">"bar"</span><span class="sy4">;</span>
    <a href="../io/cout.html"><span class="kw1762">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">"b1 = b2 calls "</span><span class="sy4">;</span>
    b1 <span class="sy1">=</span> b2<span class="sy4">;</span> <span class="co1">// implicitly-defined copy assignment</span>
    <a href="../io/cout.html"><span class="kw1762">std::<span class="me2">cout</span></span></a> <span class="sy1">&lt;&lt;</span> <span class="st0">"b1.s1 = "</span> <span class="sy1">&lt;&lt;</span> b1.<span class="me1">s1</span> <span class="sy1">&lt;&lt;</span> <span class="st0">"; b1.s2 = "</span> <span class="sy1">&lt;&lt;</span> b1.<span class="me1">s2</span> <span class="sy1">&lt;&lt;</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
<span class="br0">}</span></pre></div></div>
<p>Output:
</p>
<div dir="ltr" class="mw-geshi" style="text-align: left;"><div class="text source-text"><pre class="de1">a1 = a2 calls copy assignment of A
b1 = b2 calls copy assignment of A
b1.s1 = foo; b1.s2 = bar</pre></div></div> 
</div>
<h3><span class="mw-headline" id="Defect_reports">Defect reports</span></h3>
<p>The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
</p>
<table class="dsctable" style="font-size:0.8em">
<tr>
<th> DR
</th>
<th> Applied to
</th>
<th> Behavior as published
</th>
<th> Correct behavior
</th></tr>
<tr>
<td> <a rel="nofollow" class="external text" href="https://cplusplus.github.io/CWG/issues/2094.html">CWG 2094</a>
</td>
<td> C++11
</td>
<td> a volatile subobject made defaulted copy<br>assignment operators non-trivial (<a rel="nofollow" class="external text" href="https://cplusplus.github.io/CWG/issues/496.html">CWG issue 496</a>)
</td>
<td> triviality not affected
</td></tr>
<tr>
<td> <a rel="nofollow" class="external text" href="https://cplusplus.github.io/CWG/issues/2171.html">CWG 2171</a>
</td>
<td> C++11
</td>
<td> <span class="t-c"><span class="mw-geshi cpp source-cpp">operator<span class="sy1">=</span><span class="br0">(</span>X<span class="sy3">&amp;</span><span class="br0">)</span> <span class="sy1">=</span> <span class="kw1">default</span></span></span> was non-trivial
</td>
<td> made trivial
</td></tr>
<tr>
<td> <a rel="nofollow" class="external text" href="https://cplusplus.github.io/CWG/issues/2180.html">CWG 2180</a>
</td>
<td> C++11
</td>
<td> a defaulted copy assignment operator for class <code>T</code> was not defined as deleted<br>if <code>T</code> is abstract and has non-copy-assignable direct virtual base classes
</td>
<td> the operator is defined<br>as deleted in this case
</td></tr></table>
<h3><span class="mw-headline" id="See_also">See also</span></h3>
<ul><li> <a href="converting_constructor.html" title="cpp/language/converting constructor">converting constructor</a>
</li><li> <a href="copy_constructor.html" title="cpp/language/copy constructor">copy constructor</a>
</li><li> <a href="copy_elision.html" title="cpp/language/copy elision">copy elision</a>
</li><li> <a href="default_constructor.html" title="cpp/language/default constructor">default constructor</a>
</li><li> <a href="destructor.html" title="cpp/language/destructor">destructor</a>
</li><li> <a href="explicit.html" title="cpp/language/explicit"><code>explicit</code></a>
</li><li> <a href="initialization.html" title="cpp/language/initialization">initialization</a>
<ul><li> <a href="aggregate_initialization.html" title="cpp/language/aggregate initialization">aggregate initialization</a>
</li><li> <a href="constant_initialization.html" title="cpp/language/constant initialization">constant initialization</a>
</li><li> <a href="copy_initialization.html" title="cpp/language/copy initialization">copy initialization</a>
</li><li> <a href="default_initialization.html" title="cpp/language/default initialization">default initialization</a>
</li><li> <a href="direct_initialization.html" title="cpp/language/direct initialization">direct initialization</a>
</li><li> <a href="initializer_list.html" title="cpp/language/initializer list" class="mw-redirect">initializer list</a>
</li><li> <a href="list_initialization.html" title="cpp/language/list initialization">list initialization</a>
</li><li> <a href="reference_initialization.html" title="cpp/language/reference initialization">reference initialization</a>
</li><li> <a href="value_initialization.html" title="cpp/language/value initialization">value initialization</a>
</li><li> <a href="zero_initialization.html" title="cpp/language/zero initialization">zero initialization</a>
</li></ul>
</li><li> <a href="move_operator.html" title="cpp/language/move assignment">move assignment</a>
</li><li> <a href="move_constructor.html" title="cpp/language/move constructor">move constructor</a>
</li><li> <a href="new.html" title="cpp/language/new"><code>new</code></a>
</li></ul>

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